Single spin measurement using spin-orbital entanglement

Abstract

Single spin measurement represents a major challenge for spin-based quantum computation. In this article we propose a new method for measuring the spin of a single electron confined in a quantum dot (QD). Our strategy is based on entangling (using unitary gates) the spin and orbital degrees of freedom. An {\em orbital qubit}, defined by a second, empty QD, is used as an ancilla and is prepared in a known initial state. Measuring the orbital qubit will reveal the state of the (unknown) initial spin qubit, hence reducing the problem to the easier task of single charge measurement. Since spin-charge conversion is done with unit probability, single-shot measurement of an electronic spin can be, in principle, achieved. We evaluate the robustness of our method against various sources of error and discuss briefly possible implementations.

RevTeX4, 4 pages, some figs; updated to the published version

References in corpus (9)

• Coherent manipulation of electronic states in a double quantum dot
• Charge-based quantum computing using single donors in semiconductors
• Mesoscopic Stern-Gerlach device to polarize spin currents
• Spin-based optical quantum gates via Pauli blocking in semiconductor quantum dots
• Spin Readout and Initialization in a Semiconductor Quantum Dot
• Correlated charge detection for read-out of a solid state quantum computer
• All-Electrical Quantum Computation with Mobile Spin Qubits
• Quantum Measurement of a Single Spin using Magnetic Resonance Force Microscopy
• Single spin measurement in the solid state: a reader for a spin qubit

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• Optically induced spin to charge transduction in donor spin read-out
• Cyclic permutations for qudits in $d$ dimensions
• A multiplexed single electron transistor for application in scalable solid-state quantum computing